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Caption

A one-fourteenth scale model wave-energy machine called the 'Clam', being removed from the waters of Loch Ness, Scotland, after a trial run. If successful it would form part of the power supply to the islands and isolated communities of the region. Situated 1km from the shore in 30m of water, it consists of an aluminium cylinder, to which flexible bags are connected. The crests and troughs of the waves force air from bag to bag. The energy is extracted by air turbines in the ducting between the cylinder and bags. It is conveyed to the shore via a cable.